Engineering Board Exam Reviewer · Chemistry · medium

A first-order reaction has a rate constant of 0.0231 min-1. What is its half-life?

  1. 43.3 min
  2. 0.0160 min
  3. 30 min
  4. 15 min

Answer

C. 30 min

Solution

t1/2 = 0.693/k = 0.693/0.0231 = 30 min.

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